The invention relates to an erecting mechanism for a swivel-up rollover bar for vehicles, in particular for four-seat convertibles, having a bar leg which is supported in a swivel bearing on one vehicle side, which rollover bar can be swivelled about a transverse axis of the vehicle and has a supporting section which is remote from the swivelling axis and serves to support the vehicle during a rollover movement.
German Patent 3,732,562 discloses a U-shaped swivel-up rollover bar, the bar legs of which, which are supported at both sides on in each case one vehicle side in a swivel bearing, can be swivelled about this fixed swivel bearing. In this design of an erecting mechanism, the supporting, swivelled-up bar leg ends and the cross bar connecting them in the transverse direction of the vehicle describe a circular arc about the swivel bearing during their erection movement.
These swivel bearings of the rollover bar are generally provided in the region of the B column, i.e. approximately halfway along the length of the vehicle, since this provides a good possibility for attachment and a possibility for erecting the rollover bar which is functionally sensible. However, structural compromises in the design of the rollover bar become necessary due to the only limited installation space at the edge of a passenger compartment, which is to be as large as possible, and, where relevant, in the vicinity of a vehicle cover member which has been lowered, and, due to these compromises, the optimum erection position for support cannot always be achieved.
An object of the invention is to design an erecting mechanism for a rollover bar of the generic type by means of which the sequence of motions of the rollover bar can be matched to the conditions in the vehicle.
This object is achieved by an arrangement wherein, during the swivelling up of the rollover bar, the supporting section of the bar leg describes a curved path which deviates, at least in a partial range of the swivelling angle, from the path of a circular arc around the swivel bearing by virtue of the fact that the useful length of the bar leg is designed to vary with the stroke.
By means of a superimposed movement about the swivel bearing and in the longitudinal direction of the bar leg, it is possible to move the rollover bar in a manner matched to the installation conditions and, in addition, to adapt it in its swivel-up movement to the requirements for optimum rollover support for the vehicle. It is thereby possible both to install the rollover bar in vehicles with a limited amount of installation space for the rollover bar and to articulate them swivellably at the point in the vehicle where the conditions of support are particularly favorable. By means of this sequence of motions, it would be possible, if required, for the supporting section of the rollover bar to be moved either outside or inside of a circular arc around the swivel bearing in the extended position or to depart from the circular arc around the swivel bearing only during its erection movement, e.g. in order to circumvent a headrest, or to move inside a vehicle cover member or hood.
The control of the bar leg during its swivelling movement can be effected in preferred embodiments by means of a cam which acts on the bar leg in such a way as to displace it in the longitudinal direction. This cam can either be attached at a fixed location and the bar leg moved along it with one end, for example, or be mounted to swivel relative to the bar leg so that a rotation of the cam disc displaces the bar leg in the longitudinal direction.
The design and/or arrangement of the cam relative to the bar leg can be used to effect a large longitudinal adjustment at the beginning of the swivelling movement of the bar leg and a smaller longitudinal adjustment towards the end of the swivelling movement. This ensures, for example, that the rollover bar has already been displaced a considerable way longitudinally in any event if the overturning of the vehicle and support on the supporting section of the bar leg occurs before the bar legs have been swivelled up completely. In the end phase of the swivel-up movement, the return forces which act on the bar legs under load are then only small.
If the swivel bearing is mounted at a fixed location, the bar leg can receive particularly effective support on the vehicle side via the bearing and no additional latching means for the case of loading are necessary to support the swivel bearing.
However, it is likewise possible according to certain preferred embodiments for the bar leg to be mounted in longitudinally displaceable fashion in a bar leg housing swivellable about the swivel bearing since the locking means necessary here for locking the bar leg under load can be provided in the bar leg housing by the already familiar latching means associated with rollover bars. In this case, the cam can then be mounted swivellably on the bar leg housing.
With this erecting mechanism, the rollover bar can be raised either in the longitudinal direction of the vehicle from the vehicle side or, in the form of a U, can span the width of the vehicle with a crossbar and be supported by a bar leg on each vehicle side. On a U-shaped rollover bar arranged in this way, it is possible, if required, to provide in the crossbar a lockable connecting piece which varies the length of the crossbar and by means of which the shape of the rollover bar could, if required, be converted from a U shape to a trapezoidal shape in the raised or lowered position.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.